Tray-type humidifier



Oct 5, R` w AYRES ETAL TRAY-TYPE HUMIDIFIER Filed 001;. 4, 1962 4 Shee'GS-Shee'l'. 2

INVENTOR Pussfzz W Awars F/ G. 5 Gz-"QQGE ,4. l/AN DoHE/v, JR. BY

Oct. 5, 1965 R. w. AYRES ETAL 3,209,744

TRAY-TYPE HUMIDIFIER Filed Oct. 4, 1962 4 Sheets-Sheet 3 INVENTOR fussfu W AYRES GEORGE A l/mv oRE/v, JR.

HG. 9 BY ,M

ATTORNEY Oct. 5, 1965 R. w. AYREs ETAL 3209,744

TRAY-TYPE HUMIDIFIER Filed Oct. 4, 1962 4 Sheets-Sheet 4 INVENTOR ATTORNEY Unted States Patent Office 3,2%,7445 Patentecl Get. 5, 1965 3,2tl9,744 TRAY-TYPE HUMIDIFIER Russell W. Ayres, West St. Paul, and George A. Van

Doren, Jr., Minneapolis, Minn., assignors to Cascade Humidifiers, Inc., Minneapolis, Miun., a 'corporation of Minnesota Filed Oct. 4, 1962, Ser. No. 228,454 6 Claims. (Cl. 126-113) This invention relates to an improvement in humidifier and deals particularly with an apparatus which is connected to the air ducts |of a hot air circulating and heating system to add moisture to the air being distributed by the system.

Various types of humidifiers have been produced for use in conjunction with hot air heating systems. Some of the earlier types of such systems include merely trays which are mounted on or incorporated with the hot air furnace and over which the air is directed. These trays 'are filled with water from a suitable supply, and air is circulated over the trays in an eifort to pick up moisture. For the most part, such arrangements have been ineffective for their intended purpose. Other arrangements have been used in which the water is divided into a fine spray by suitable Operating means and picked up by the hot air system. Such larrangements not only require, in most instances, power to operate, but also cease functioning efectively after a short period of time due to the deposit of minerals on the screens or other supports against which the moisture is sprayed. The pan type evaporators are also usually non-effective after a short period of time due to the collection of impurites which are deposited in the tray upon the evaporization of the water. It is an object of the present invention to provide a humidifier which avoids these previous difficulties.

It is .an object of the present invention to provide a humidifier which includes a series of superimposed trays, each of which is designed to accommodate a predetermined depth of water. The `structure is such that water flows from a suitable supply into the uppermost tray, and dr-ains continually from one tray to the next so that all of the trays contain water. The air being circulated in the heating system is transmitted through the stack of Water trays, so that much of the circulated air is given ;an opportunity of picking up moisture. This system differs from the usual tray system in that the amount of water circulated is considerably in excess of that required to humidify the area being heated. As a result, there is a constant flow of fluid through the system and the concentration of impurities in the water never decreases to the point where they will deposit in the trays. As a result, the trays remain continuously clean, and need no attention over a considerable period of time.

An added feature of the present invention resides in the provision of a series of trays which .are in superimposed relation, and which are supported with the marginal edge of one tray slightly below the bottom of the next above tray. Each of the trays includes a bottom panel, an upwardly and outwardly inclined wall connected to the bottom panel, and a peripheral flange encircling the walls. The arrangement is such that as the air passes between the trays, the inclined walls tend to defiect the air downwardly toward the surface of the liquid in the trays which is maintained at a level below the peripheral fiange. Thus the air has a good opportunity of picking up moisture during its passage between the trays.

A further feature of the present invention resides in the provision of a humidifier of the general type described in which the trays may all be of identical form. Each tray is of generally rectangular outline, and includes a drain aperture including a generally frusto-conical flange extending upwardly for a short distance, a ring-shaped flange extending inwardly from the top of the frustoconical fiange, and a down-turned flange at .the inner edge of the ring-shaped flange which acts to guide the water smoothly into the next pan. Each drain opening is positioned nearer one end of the tray than to the other, and the trays are alternately reversed so that the water will drain through one end of the top tray and the other end of the next, etc. This arrangement also permits the lowermost tray to be connected to a drain by a tube which terminates between the frusto-conical flange and the downturned flange without necessarily being actually connected thereto.

A further feature of the present invention resides in the provision of a novel and effective means of leveling the tray so that they may be constantly maintained -in level position. The four corners of the trays are held in equally spaced relation by spacer sleeves through which rods having threaded ends are inserted. The spacers and connect'ing rods along one side of the trays are held in position by nuts which merely maintain the trays in parallel relation. The threaded rods supporting the oth'er two corners of the tray are also provided with nuts which clamp the trays in equally spaced relation. However, these last two rods are elongated to extend through top and bottom brackets, at least some of which are slotted along parallel planes. Nuts -are provided on the threaded rods to engage opposite sides of the bracket so that one end 'of the trays may be raised or lowe-red relative to the other by adjustment of the nuts relative to the bracket. The t-rays can be leveled in the other direction by adjustment of the rods in the slots until they are Vertical, thereby holding all of the parallel trays level through the use of two supporting bolts.

An added feature of the invention in the preferred form thereof resides in the connection of the humidifier between a pair of parallel Vertical plenums, one of which forms the hot air plenum leading from the furnace, and the other of which comprises the return duct leading to the intake of the furnace heating chamber, the two plenums or ducts being usually parallel and eXt-ending Vertically. The Chamber enclosing the humidifier is in communication with apert-ures cut in the two ducts, at least one of which may be closed to eliminate circulation through the humidifier. In view of the fact that the hot air duct is usually Operating at a pressure somewhat above atmospheric pressure while the furnace is in operation, and the return air duct is Operating at la pressure somewhat less than atmospheric pressure, the pressure differential causes a natural circulation of air through the humidifier 'so that heated air from the hot air duct is mostened, and drawn linto the return air duct to be reheated and reci-rculated.

An added feature of the present invention resides in the provision of a water supply valve controlling the supply of water to the humidifier and which yis operated by variations in temperature within the humidifier housing. This arrangement is such that the water supply to the humidifier will be cut oif until the air circulated from the furnace heats the interior of the humidifier cabinet to the point where the water supply will be automatically turned on. In the meantime, the air will circulate over the water remaining in the humidifier from the previous cycle of operation.

A further feature of a modified form of construction of the invention resides in the provision of a scoop or baffle member designed to eXtend into the hot air plenum of the furnace when the humidifier is mounted upon this plenum alone. The scoop is hingedly connected to the humidifier, for example, to the uppermost tray, and is adjnstable to eXtend a greater or lesser distance into the plenum. Obviously, the greater distance the scoop extends into the plenum, the more heated air Will be de- J flected to pass through the humidifier. A space is provided communicating the upper portion of the humidifier chamber with the interior of the plenum so that the humidified air may rise and pass back into the plenum.

These and other objects and novel features of the present invention will be more clearly and fully set forth in the following specification and claims.

FIGURE l is a perspective view of the humidifier in osition connecting the hot air duct with the return air FIGURE 2 is an exploded view of the humidifier cabinet to show the general arrangement of the cabinet and its attachment to the two ducts.

FIGURE 3 is a horizonta] sectional view through the cabinet and the ducts showing the general arrangement thereof. The humidifier itself is omitted from FIGURE 2 in order to show the housing, and is shown in dotted outline only in FIGURE 3 of the drawings.

FIGURE 4 is a Vertical sectional view through the humidifier and its cabinet.

FIGURE 5 is a top plan view of one of the trays ot the humidifier.

FIGURE 6 is a perspective view of a modified form of humidifier, a portion of the housing as well as the supporting brackets being broken away to show the interior thereof.

FIGURE 7 is a transverse sectional view through the humidifier illustrated in FIGURE 6.

FIGURE 8 is a perspective view of the baffle or scoop showing the construction thereof.

FIGURE 9 is an elevational view of the water control valve used in conjunction with the humidifier.

FIGURE 10 is a diagrammatic view of another modified form of construction.

FIGURE 1 of the drawings indicates a typical arrangement of humidifier mounting which is to be preferred. The humidifier A is supported bridging the hot air duct 10 leading from the furnace B and the cold air duct 11 extending from the heated area to the furnace where the ducts 10 and 11 are arranged in horizontally spaced relationship as illustrated. The humidifier A may be mounted to overlie a pair of generally rectangular apertures 12, 13 in the ducts 10 and 11 to coincide with the laterally spaced apertures 14 and 15 located in the rear panel 16 of the housing 17 of the humidifier. The housing panel 16 is secured in face contact to the ducts 10 and 11 by sheet metal screws or other suitable means extending through apertures 19 and into the ducts. A rectangular peripheral fiange 20 extends forwardly from the mounting plate 16 for attachment with the remainder of the housing which will be later described.

A damper or fiow control plate 21 may be sandwiched between the surface of one of the ducts and the mounting panel 16 for controlling the air fiow through the apparatus. The panel '21 is provided with a right angular flange 22 along one edge by means of which the panel 21 may be grasped and moved, and includes a second flange 23 along its opposite edge which may extend into one of the openings such as 13 so as to limit movement of the plate 21. By sliding the plate 21 in one directon or the other, the size of the opening 13 may be eifectively varied to control the amount of air by passing through the humidifier housing.

The particular housing 17 illustrated includes a bottom panel 24 connected at opposite ends to upstanding end panels 25, the panels 24 and 25 being reinforced by coplanar flanges 26 and 27 along the front and rear edges thereof. The fianges 26 and 27 on the inner edges of the panels 24 and 25 are secured in face contact with the mounting plate 16 forming the inner wall of the housing. Angularly related top panel 29 and outer wall 30 are similarly provided with right angularly extending reinforcing flanges 31 and 32, respectively, which telescope over the edges of the end walls 25 to complete the rectangular housing. The angularly related top panel 29 and forward wall panel 30 are held assembled to the remainder of the housing by means of a suitable screw 33. The means employed for securing the panels 24 and 25 to the mounting panel 16 are not illustrated, and these parts may be spot welded or otherwise secured together as the humidifying unit is readily accessible by removing the combined panels 29, 30.

The humidifier unit includes a series of superimposed trays 34 of generally rectangular outline. Each tray 34 includes a generally rectangular bottom panel 35 having upwardly and outwardly inclined end walls 36, and upwardly and outwardly inclined connected side walls 37 forming a shallow tray-shaped body. A peripheral planar flange 39 extends outwardly from the upper edge of the connected side and end walls 37, 36. The corners of the tray are apertured as indicated at 40 to accommodate the supporting means. The bottom 35 of each tray is also provided with an outlet which is preferably formed by a short upwardly extending outer sleeve 41, and inwardly extending ring-shaped flange 42 integral with the upper edge of each sleeve 41, and a down-turned flange 43 on the inner edge of the ring shaped flange 42. This provides a rounded or smooth upper surface over which the water may fiow in leaving the tray. As is indicated, the ring-shaped fiange 42 is considerably below the level of the peripheral flange 39 so that the layer of water within the humidifier is very shallow. The purpose of this arrangement will be later described. The fianges 43 which define the outlet openings 44 are shown midway between the side walls 37, but nearer one end Wall`` 36 than to the other. In view of the fact that the trays are otherwise symmetrical, alternate trays are turned end for end to provide a tortuous path of fiow for the liquid, alternate outlet openings being aligned. The shape of the outlets permits a drain pipe 45 to be inserted through an opening 46 in the bottom panel 24 and into the channel formed between the flanges 41 and 43 on the under surface of the lower tray, eliminating the requirement for a solid connection or solid joint.

A pair of angle brackets 47 are secured against the mounting panel 16 and terminate in forwardly turned ends 49 which are arranged in a common horizontal plane. A similar pair of angle brackets 50 are also secured inwardly of the mounting panel 16 near the bottom thereof, the brackets 50 having forwardly extending ends 51 which are also on a common horizontal plane. The parallel bracket ends 49 and 50 are apertured to accommodate Vertical threaded mounting rods 52, and at least one pair of bracket ends 49 or 51 are slotted in planes normal to the mounting plate 16 to permit the leveling of the unit by tilting the assembled unit forwardly or rearwardly.

While FIGURE 7 of the drawings shows a modified form of construction, the humidifying unit itself is identical to that shown in FIGURE 4, and the mounting of the unit may be best understood by an examination of FIGURES 4 and 7. As noted, the trays 34 are held in spaced relation by spacer sleeves 53 which are held in place by vertically extending bolts 54 which extend through the sleeves in the forward corners of the trays and through the apertures 40 in the trays, the bolts 54 thus solidly bolting the forward corners of the trays together. The threaded rods 52 extend through similar sleeves 53 between the rear corners of the trays, and the trays are held together by nuts 55 on the threaded rods 52 intermediate the ends thereof. Thus all of the four corners of the trays are securely bolted together to form a solid unit.

It is indicated in the drawings, the upper and lower ends of the threaded rods 52 eXtend through the horizontal bracket portions 49 and 51, and adjustment nuts 56 and 57 permit the individual adjustment of the rods 52. The trays 34 are leveled horizontally in a transverse directon by raising or lowering one of the rods relative to the other. The trays are leveled on a forward and a rear directon by tilting the rods 52 With respect to the end 49 or 51 of the slotted bracket. In other words, if the ends 49 of the lbrackets 47 are slotted, the upper ends of rods 52 may be swung forwardly or rearwardly in the slot of the bracket end 49. Thus the trays may be leveled in a very simple manner after the housing has been installed so that there is a layer of water of equal depth in the bottom of each of the trays while the device is in use.

In operation, the apparatus is installed in place, and the automatic valve unit 60 is mounted on one of the four corners of the uppermost tray to overlie this tray. The valve 60 is shown in FIGURE 9 as extending through the Vertical flange 61 of an angle bracket 62, and the shank of the Valve is secured in place by the nut 63. The valve is opened and closed by means of a cap 64 which is moved axially of the valve body by means of an arm 65. Movement of the arm 65 is controlled through the adjustment bolt 66 by a strip of bimetallic metal 67 having an -end flange 69 held in place against the bracket arm 61 by the nut 63. The purpose of the valve unit 60 is open the water supply only when the furnace is in operation and the ambient temperature within the humidifier housing is increased to the extent necessary to operate the valve 60.

Thus when the furnace B starts in operation, air is circulated through the humidifier housing and over the plates, picking up moisture during the operation. The circulation of air through the humidifier unit is insured by the fact that the air within the hot air duct is under slight pressure while the air passing downwardly through the return duct 11 is under slight vacuum thus causing a natural circulation of air due to the dilferential in pressure between the ducts 10 and 11. The amount of circulation may be varied by adjustment of the control plate 22 which more or less opens one of the duct openings such as 13.

It is important that the valve 60 be arranged to supply an amount of water considerably in excess of the actual requirements so that during the operation of the device, there is a constant flow of water to the tray. Obviously, this increases the cost of operation and makes the unit less economical than would be the case if all of the moisture were evaporated into the air. However, this process is employed, for in this way the moisture will never deposit impurities such as metal salts and the like upon the trays. Tests using the unit over a period of years has proven that the device will function as described without depositing foreign materials in the trays due to the fact that the concentration of these impurities is never allowed to increase to the point where they will precipitate.

FIGURES 6, 7, and 8 of the drawings show a modified means of installing the apparatus which is preferred if the hot air duct and return duct are not in proper side by side relationship. In view of the fact that the unit itself is identical to that previously de'scribed, the same identifying numerals for the identical parts have been employed.

The structure shown in FIGURES 6 and 7 are shown as including a one-piece housing 70 having a front panel 71, integral top and bottom panels 72 and 73, and parallel side panels 74. Top and bottom fianges 75 and 76 extend upwardly and downwardly respectively from the rear edges of the top and bottom panels 72 and 73, and laterally extending flanges 77 extend laterally from the end walls 74. The flanges 75, 76, and 77 are secured to the hot air duct 79 leading upwardly from the furnace B by suitable bolts such as 80. A rectangular opening 81 is provided in the duct 79 in registry with the interior of the housing 70. The main difference in the construction illustrated in these figures lies in the provision of a scoop or bafiie 82 which extends into the interior of the duct 79 to permit a predetermined portion of the hot air to be directed through the humidifying unit. As indicated in FIGURE 8 of the drawings, the scoop 82 includes an inclined baffle plate 83 connected along its side edges to a pair of generally triangular scoop sides 84. An extending tongue 85 is provided to overlie the forward edge of the humidifying unit between the threaded supports 52. Hinges 86 are secured to the upper corners of the panel 83 and are provided with apertured plates 87 which are designed to accommodate the two thread'ed rods 52. Thus the scoop 82 is held in hinged relation to the humidifier unit by a pair of nuts 89 on the upper portion of the rods 52 overlying the nuts 55.

As indcated in FIGURE 6 of the drawings, an adjusting arm 90 is hingedly connected at 91 to the scoop side 84, and extends through registering slots 92 in the duct 79 and flange 77. The arm 90 is provided with notches 93 along its lower edge which are designed to engage the lower edge of the slot 92 to hold the arm in an adjusted position. Through the use of the arm 90 the scoop 82 may be hinged to extend across the greater or lesser percentage of the duct 79, thus directing more or less of the heated air through the unit between the trays. The air rises above the level of the trays and returns to the duct 79 above the level of the unit.

FIGURE 10 of the drawings shows another modified form of construction. In this arrangement, the tray unit is merely supported in a horizontal air duct 95, and is supplied with water through a supply line 96, and is provided with a drain pipe 97 leading to a suitable drain. The air through the unit may be regulated by a baifie plate 99 which extends transversely through a greater or lesser amount of the duct to permit the air to either flow around the unit or through it as desired. This unit may be desirable in installations where a portion of the horizontal air duct extends above the level of a convenient drain.

The operation of the apparatus can be made fully automatic by the addition of a solenoid valve in the water supply line, and in providing a humidistat for controlling the circuit to the solenoid` Such a system has the advantage of eliminating the necessty of adju-sting the fiow of air through the humidifier, and makes the system operate completely automatically.

In accordance with the patent statutes, we have described the principles of construction and operation of our improvement in humidifier, and while we have endeavored to set forth the best embodiment thereof, we desire to have it understood that changes may be made within the scope of the following claims without departing from the spirit of our invention.

We claim:

1. A humidifier apparatus including,

a series of superimposed trays,

means supporting said trays in vertically` spaced relation,

each said tray including a bottom panel, encircling upwardly and outwardly inclined walls, and a peripheral planar flange, the bottom of each tray above the lowermost tray being in a plane closely adjacent to the plane of the planar flange of the tray next below,

the bottom panel of each tray including an upwardly extending sleeve defining an outlet nearer one end of the panel than the other,

the outlets of alternate trays being staggered with respect to the others,

the sleeves terminating at a level substantially below the level of said flange,

the upper ends of said sleeves including an inwardly extending ring shaped flange terminating in a 'downwardly turned fiange ending substantially on the plane of the bottom panel of the tray,

a water inlet supported above the uppermost tray for supplying water thereto,

a drain supported in communication with the outlet Of the lowermost tray, and

means to direct air toward peripheral edges of the trays,

7 Whereby air passing between said trays is defiected downwardly toward the water in the tray next below by the inclined walls of the trays. 2. The structure of claim 1 and in which said means to direct air toward peripheral edges of said trays includes, a housing enclosing said trays, land means securing said housing in communication with a hot air duct and a return air duct to create 'an air flow through said housing from said hot air duct to said return air duct. 3. A humidifier for use in combination with a hot air duct and including a series of superimposed generally rectangular trays arranged in spaced, parallel continguous relation,

each of said trays includes a drain opening therethrough through which liquid may drain from one pan to another,

spacer means between the corners of said trays to hold the same equally spaced,

fastening means extending through each of two adjoining corners of the trays along one side thereof for holding the trays 'assembled,

threaded rods extending through the remaining corners of said trays to hold the trays assembled, and extending above and below said trays,

bracket means arranged in pairs 'above and below said trays for supporting said trays and through which the upper and lower ends of said threaded rods extend, nuts on said threaded rods engageable with said briackets to hold said trays in adjusted relation and adapted to permit adjustment of the elevation of said trays on a plane through the axes of said threaded means,

at least one pair of said brackets being slotted to permit adjustment about an axis passing through the points of engagement of said threaded rods with the brackets of the other pair, and a water inlet for directing water to the uppermost tray of said series.

4. The structure of claim 3 and in which said humidifier includes an enclosing housing adapted for connection with an air duct and in which said brackets are secured to said housing.

5. A humidifier apparatus including,

a series of superimposed trays,

means supporting said trays in vertically spaced relation,

each said tray including a bottom panel, encircling upwardly 'and outwardly inclined walls, and a peripheral planar flange, the bottom of each tray above the lowermost tray being in a plane closely adjacent to the planar flange of the tray next below,

means to direct air toward peripheral edges of the trays,

the bottom panel of each tray including an upwardly extending sleeve defining an outlet nearer one end of the panel than the other,

the outlets of alternate trays being staggered with respect to the others,

the sleeves terminating at a level substantially below the level of said flange,

a water inlet supported above the uppermost tray for supplying water thereto,

a drain supported in communication with the outlet of the lowermost tray,

whereby air passing between said trays is de'flected downwardly toward the water in the tray next below by the inclined walls of the trays,

said water inlet terminating in a horizontally extending outlet pipe,

a cap axially slidable on said pipe and including a valve seat engageable against the end of said outlet pipe in one extreme position thereof,

an open bottomed enclosure enclosing said cap and outlet pipe,

a lever arm hinged to said enclosure and to said cap to slide said cap, and

a bimetallic strip secured overlying said enclosure and connected to said lever arm to activate the same to slide said cap into and out of said one extreme position.

6. A humidifier apparatus including,

a series of superimposed trays,

peripherally spaced externally threaded rods extending through said trays,

spacer sleeves of equal height encircling said rods between each tray and the next adjoining tray to hold said trays in vertically spaced relation,

means on the ends of said rods for holding said trays assembled,

two adjoining of said rods extending above and below said series of trays,

brackets above and below said series of trays through which said two rods extend,

nuts on the upper and lower ends of said rods engageable with said trays to permit individual height adjustment of said trays,

at least one of said brackets through which each of said rods extends being slotted to permit adjustment about an axis passing through the points of engagement of the threaded rods with the other brackets.

References Cited by the Examiner UNITED STATES PATENTS 188,535 3/77 Parmenter 261-114 1,418,296 6/ 2,2 Gohmann. 2,105,773 1/38 Magney 126-113 X 2,565,210 8/51 Dovolis 126-113 2,682,395 6/54 Claridge et al 261-114 2,766,027 10/56 Herr 126- 113 2,805,660 9/57 Coleman et al 126 113 2,806,466 9/57 Thompson 126-113 2,858,825 11/58 Skerritt 126 113 3,092,096 6/63 Nett et al 126-113 3,105,860 10/63 Dunn 126-113 FOREIGN PATENTS 258 8/77 Germany. 253,469 3/48 Switzerland.

IAMES W. WESTHAVER, Primary Examner. 

1. A HUMIDIFIER APPARATUS INCLUDING, A SERIES OF SUPERIMPOSED TRAYS, MEANS SUPPORTING SAID TRAYS IN VERTICALLY SPACED RELATION, EACH SAID TRAY INCLUDING A BOTTOM PANEL, ENCIRCLING UPWARDLY AND OUTWARDLY INCLINED WALLS, AND A PERIPHERAL PLANAR FLANGE, THE BOTTOM OF EACH TRAY ABOVE THE LOWERMOST TRAY BEING IN A PLANE CLOSELY ADJACENT TO THE PLANE OF THE PLANAR FLANGE OF THE TRAY NEXT BELOW, THE BOTTOM PANEL OF EACH TRAY INCLUDING AN UPWARDLY EXTENDING SLEEVE DEFINING AN OUTLET NEARER ONE END OF THE PANEL THAN THE OTHER, THE OUTLETS OF ALTERNATE TRAYS BEING STAGGERED WITH RESPECT TO THE OTHERS, THE SLEEVES TERMINATING AT A LEVEL SUBSTANTIALLY BELOW THE LEVEL OF SAID FLANGE, THE UPPER ENDS OF SAID SLEEVES INCLUDING AN INWARDLY EXTENDING RING SHAPED FLANGE TERMINATING IN A DOWNWARDLY TURNED FLANGE ENDING SUBSTANTIALLY ON THE PLANE OF THE BOTTOM PANEL OF THE TRAY, 